This invention relates to an amalgam retainer for an arc discharge lamp and more particularly to an amalgam retainer for an electrodeless lamp.
Many arc discharge lamps rely for operation on the presence of mercury in the arc stream. The mercury is present, when the lamp is not operating, as elemental mercury or as a solid or liquid amalgam. In some types of lamps, particularly electrodeless fluorescent lamps such as those shown in U.S. Pat. Nos. 6,175,197 and 5,834,905, it is important to keep the solid or liquid amalgam from settling within the arc environment where it can cause changes in the lumen output and the lumen-temperature performance of the lamp. This is particularly true in those instances where the amalgam includes bismuth.
It is, therefore, an object of this invention to obviate the disadvantages of the prior art.
It is another object of the invention to enhance to operation arc discharge lamps.
It is yet another object of the invention to enhance the operation and life of electrodeless fluorescent lamps.
These objects are accomplished, in one aspect of the invention by providing an arc discharge lamp that has an arc chamber with an amalgam tip attached to and communicating with the arc chamber through an elongated narrow tube which projects into the amalgam tip. An amalgam is contained within the amalgam tip. The amalgam tip contains sufficient volume to contain the amalgam when in a liquid or solid state and the narrow tube permits the necessary mercury vapor to enter the arc chamber. The construction allows operation of the lamp in any position, including one with the amalgam tip uppermost.